GST on Interest on Saving or FD

Yes. It is supply of Service but Exempt under notification.

Entry  No. 27 of Notification No. 12/2017- Central Tax (Rate):

Transaction in money where consideration is represented by Interest is supply under GST but the same has been exempted from the purview of GST through exemption notification.

So currently there is no GST on Interest income on deposit.

Thank you so much. Yes it is in exemption as mentioned by Mitul.